/**
* @author AlbertDarren
* @contact 2563491540@qq.com
*/
#include <cstdio>

using namespace std;
int intSeq[20]={0};
int main_83()
{
    int n,x,idx=-1;
    scanf("%d",&n);
    for (int i=0;i<n ;++i )
    {
        scanf("%d",&intSeq[i]);
    }
    scanf("%d",&x);
    for (int i=0;i<n ;++i )
    {
        if (intSeq[i]==x)
        {
            idx=i+1;
            break;
        }
    }
    if (idx!=-1)
    {
        printf("%d\n",idx);
    }
    else
    {
        printf("NO\n");
    }
	return 0;
}
